BR Class 502 & Class 503 orginal designation

[Kubsamboll]

Hi everyone,

I am writing to ask about the BR Class 502 and Class 503 electric multiple units, and more specifically, what designation they had before the introduction of TOPS and before nationalisation?

 

[Snow1964]

I think numeric codes only came later.

Not sure what names they had whilst changeover from original L&Y stock was in transition, but 503s became known as Wirral units, or Wirral electrics (units was not common in 1940s when sets tended to be common parlance). I'm not so sure about the name for 502s

 

[AndrewE]

Wikipedia https://en.wikipedia.org/wiki/British_Rail_Class_503 says (of the 503s) "When introduced by the LMS, they were known officially as Class AM3" so it's reasonable to guess that the 502s might have been AM2.

I hadn't realised that the 2 types were so different, vehicle width, length and buffers/couplings, power etc

 

[Fleetwood Boy]

Wikipedia https://en.wikipedia.org/wiki/British_Rail_Class_503 says (of the 503s) "When introduced by the LMS, they were known officially as Class AM3" so it's reasonable to guess that the 502s might have been AM2.

I hadn't realised that the 2 types were so different, vehicle width, length and buffers/couplings, power etc

Not sure that’s right.

The A part refers to AC doesn’t it, and surely the Blue Trains that became class 303 were previously AM3?

Although there would be a logic for a DM series of codes for DC multiple units, I’ve never heard of such a thing?

 

[Merle Haggard]

Wikipedia https://en.wikipedia.org/wiki/British_Rail_Class_503 says (of the 503s) "When introduced by the LMS, they were known officially as Class AM3" so it's reasonable to guess that the 502s might have been AM2.

I hadn't realised that the 2 types were so different, vehicle width, length and buffers/couplings, power etc

The AM3 designation was introduced long after the LMS had ceased to exist, and the 'A' letter meant 'A.C.'
The AM2/3 designation became the 302/3
Wikipedia ...

 

[30907]

The AM3 designation was introduced long after the LMS had ceased to exist, and the 'A' letter meant 'A.C.'
The AM2/3 designation became the 302/3
Wikipedia ...

To be fair, W... references Colin Marsden, normally a reliable author, and is aware of the potential confusion. I agree that AM... makes no sense.

 

[The exile]

Would they have had anything official at all? The LMS (and GWR) didn’t use codes for loco classes, so why would the units (which were even more localised and easy to “keep tabs on”) be any different?

 

[EyeKay]

I would agree that the Glasgow blue trains were AM3

 

[Magdalia]

Wikipedia is not a reliable source, this was discussed very recently here:

Getting Your Railway Facts Wrong

I try as always to get my railway facts correct, but due to more and more documents being made available online I'm now going to have to re-write the early history of the branch line I have been researching. My original source of information about the branch line comes from a well written L&Y...

www.railforums.co.uk

The reason I call them 'Zombies' is the fact that once 'old' views are in print, often in 'authoritative' sources, they are often almost impossible to kill. Revisions are frequently in specialist historical journals/websites, and non-specialists will have no idea they exist. So long-dead ideas keep getting recycled in 'popular' books, magazines and websites (including Wikipedia, where I have on occasion been reverted multiple times when trying to correct Zombies ...).

Unfortunately, in many areas Wikipedia's editorial policy actively prevents such corrections - an untruth repeated often enough must be true, because it has been repeated so often. And if the evidence that it is untrue is found in a primary source, it can't be referred to because the source might be biased!

I have an old Ian Allan Combined Volume with the BR fleet as at end December 1967. I think it is the last before class numbers were introduced.

The EMU cars M28311M-M28369M are entitled Liverpool-Southport two and three car open sets.

The EMU cars M28371M-M29289M are entitled Wirral & Mersey three car open sets.

the Blue Trains that became class 303 were previously AM3?

That's what it says in the same source. These are also entitled Glasgow suburban three car units.

The reliable original source would be the diagram books, but I don't have one of those for EMUs.

 

[Big Jumby 74]

I have an old Ian Allan Combined Volume with the BR fleet as at end December 1967. I think it is the last before class numbers were introduced.

The EMU cars M28311M-M28369M are entitled Liverpool-Southport two and three car open sets.

The EMU cars M28371M-M29289M are entitled Wirral & Mersey three car open sets.

I would concur. Taking the 1959 combined volume, with the exception of the Southern who gave their electric units a descriptive code, eg: 2 NOL etc, the other regions electric units were just given an area (of operation) type description, so for Merseyside there was 'Liverpool-Southport' stock and 'Wirrel & Mersey' stock.

 

[eastwestdivide]

Colin Marsden, normally a reliable author

… for certain values of ‘reliable’…

 

[hexagon789]

The reliable original source would be the diagram books, but I don't have one of those for EMUs.

The Barrowmore Model Railway Group have some BR diagram books available to view on their website, if that's any use?

 

[Magdalia]

The Barrowmore Model Railway Group have some BR diagram books available to view on their website, if that's any use?

Good thinking. They are here, lots of them.

Barrowmore Model Railway Group (BMRG)

Group members have collected together a number of documents over time that we feel other modellers would appreciate access to. You'll find these below: we hope to add to these in the future.

BRB Vehicle Diagram Book No.210

This gives the following:

Class 502

DMBS design code EB202 ex diag LMS 345
DTS design code EE207 ex diag LMS 393
TS design code EH202 ex diag LMS 379

Class 503

DMBS design code EB203 ex diag LMS 344A
DTS design code EE202 ex diag LMS 392A
TS design code EH214 ex diag LMS 368A

I couldn't get it to do copy and paste so hopefully I have transcribed without errors!

 

[30907]

… for certain values of ‘reliable’…

I should perhaps have said "reputable" - anyway in this case WP may not be to blame but a source.

 

[Springs Branch]

I have an old Ian Allan Combined Volume with the BR fleet as at end December 1967. I think it is the last before class numbers were introduced.

The EMU cars M28311M-M28369M are entitled Liverpool-Southport two and three car open sets.

The EMU cars M28371M-M29289M are entitled Wirral & Mersey three car open sets.

The LMR Sectional Appendix for 1960 has three or four references here & there to what would become Class 502s, with local instructions relating to this stock (mostly, it seems, connected with their unusual width)

One extract (from page 198) is attached below.

In all mentions within the Sectional Appendix they are referred to as Liverpool and Southport Electric Sets or Cars or Stock (no mention of 'units' or 'EMUs' in those days). So, BR Officialdom and Ian Allan seem to concur on that.

My Central Lines document does not extend to lines across the Mersey, so I can't confirm what BR called the 503s back then - although IA's Wirral & Mersey sets sounds highly plausible.

 

[M28361M]

I hadn't realised that the 2 types were so different, vehicle width, length and buffers/couplings, power etc

Yes, a lot of people seemed quite indifferent when the 503 was scrapped because the preserved 502 still existed, but they are completely different trains. The 502 group were offered components from the 503 but apart from a few fixtures and fittings there is almost nothing usable because the classes have little in common.

Not sure that’s right.

The A part refers to AC doesn’t it, and surely the Blue Trains that became class 303 were previously AM3?

Although there would be a logic for a DM series of codes for DC multiple units, I’ve never heard of such a thing?

I haven't seen Colin Marsden's book which is given as a reference for this designation, but I think it is implied that the AM3 here was an LMS thing completely separate to the much later BR usage. Or it could just be a mistake. If anyone has a copy of the book it would be interesting to see what it actually says.

 

[Taunton]

I hadn't realised that the 2 types were so different, vehicle width, length and buffers/couplings, power etc

They were, although overhauls at Horwich works for both led to the appearance, both exterior and interior, looking much the same, with common seating fabrics, pale grey paint, and system maps on the ceiling.

I believe the 503s were officially styled "Wirral & Mersey" units, right from the start when they operated through from the onetime Wirral Railway onto the then-independent (until 1948 nationalisation) Mersey Railway. They were effectively clones of the London Underground O and P stock of the same era, by the same builders and doubtless done in the same drawing offices, along with construction also being very equally shared between Met-Cam and Birmingham RCW. LMS Derby works then came up with their version for the Southport units, with among other things conventional buffers (huge ones) and drawgear, compared to the Wirral Buckeyes and no buffers, so they were quite incompatible with one another. This among other things led to hesitance, and then abandoning, the short term use of a few spare Wirral units on the newly electrified Kirkby line in the late 1970s, it causing great issues in recovering a failed unit if the opposite type was behind.

 

[Mogz]

The LMR Sectional Appendix for 1960 has three or four references here & there to what would become Class 502s, with local instructions relating to this stock (mostly, it seems, connected with their unusual width)

One extract (from page 198) is attached below.

In all mentions within the Sectional Appendix they are referred to as Liverpool and Southport Electric Sets or Cars or Stock (no mention of 'units' or 'EMUs' in those days). So, BR Officialdom and Ian Allan seem to concur on that.

My Central Lines document does not extend to lines across the Mersey, so I can't confirm what BR called the 503s back then - although IA's Wirral & Mersey sets sounds highly plausible.
View attachment 172747

That is interesting.

I remember seeing a picture of the entrance to Liverpool Central Low Level shortly after nationalisation which said “To Wirral and Mersey Lines”.

Presumably the line to Rock Ferry was the “Mersey Line” with the lines to West Kirby and New Brighton being the “Wirral Line” in those days?

Getting back to the stock, I believe the “M” prefix was given to what later became the 502 and 503 classes shortly after nationalisation (source: Merseyside Memories - Vol.2- The Loop and Link).

 

[eastwestdivide]

I believe the “M” prefix was given to what later became the 502 and 503 classes

M prefix (and suffix as well, surely?) to the coach numbers would be a nationalisation thing. The prefix to denote “owning” region, and the suffix to distinguish number series from the pre-nationalisation groups. Some of those number series were carried on for coaches built by BR to designs by the big four.

 

[Taunton]

That is interesting.

I remember seeing a picture of the entrance to Liverpool Central Low Level shortly after nationalisation which said “To Wirral and Mersey Lines”.

Presumably the line to Rock Ferry was the “Mersey Line” with the lines to West Kirby and New Brighton being the “Wirral Line” in those days?

Getting back to the stock, I believe the “M” prefix was given to what later became the 502 and 503 classes shortly after nationalisation (source: Merseyside Memories - Vol.2- The Loop and Link).

The independent Mersey Railway ran from Liverpool Central to Rock Ferry and to Birkenhead Park. At the latter it made an end-on junction with the Wirral Railway (LMS from 1923) to New Brighton and West Kirby. The Mersey was an electrification pioneer in 1903, and passengers changed at Rock Ferry or Birkenhead Park into services of the other companies. The first batch of 503s came with the electrification of the Wirral lines beyond Birkenhead Park in 1938, the new LMS trains and the old Mersey trains running through, in an arrangement which balanced the mileage proportions between each. In 1956 the old Mersey trains were finally replaced by trains which were complete copies of the 1938 stock, by the same builders as before.

The Mersey used a 4-rail electric scheme, like London Underground, whereas the later Wirral scheme was 3rd rail, so both Mersey and Wirral trains had changeover switches for when at Birkenhead Park they ran on from one to the other, until finally standardised as 3rd rail throughout in the late 1950s.

 

[Springs Branch]

I remember seeing a picture of the entrance to Liverpool Central Low Level shortly after nationalisation which said “To Wirral and Mersey Lines”.

Presumably the line to Rock Ferry was the “Mersey Line” with the lines to West Kirby and New Brighton being the “Wirral Line” in those days?

It could be slightly more complicated than that. Historical company differences persisted long after nationalisation, and it wasn't necessarily one branch from Hamilton Square versus the other.

The booking offices for Central Low Level were below ground, in a grotty, congested subway in the days before rebuilding for the Link & Loop. Being a very busy station, there were multiple ticket windows, but you needed to take care to go to the right one, even for tickets for short local journeys.

IIRC the ticket windows were labelled with big notices, saying something like "Beyond Park" (which for the uninitiated meant anywhere beyond Birkenhead Park to West Kirby & New Brighton) and "All Stations to Park & Rock Ferry". There may have been a third permutation for "Beyond Rock Ferry" if you were continuing further down the Wirral for a day out to Chester or Rhyl. I don't know what happened if a hapless visitor wanting Birkenhead North queued at the "All to Park" window; did he get re-directed to the back of the queue at an adjacent window for being one stop too far?

All a hangover from days when the Mersey Railway and Wirral Railway / LMS ran their own separate booking offices - and sobering (for me) that it continued into my lifetime.

The independent Mersey Railway ran from Liverpool Central to Rock Ferry and to Birkenhead Park. At the latter it made an end-on junction with the Wirral Railway (LMS from 1923) to New Brighton and West Kirby. The Mersey was an electrification pioneer in 1903, and passengers changed at Rock Ferry or Birkenhead Park into services of the other companies. The first batch of 503s came with the electrification of the Wirral lines beyond Birkenhead Park in 1938, the new LMS trains and the old Mersey trains running through, in an arrangement which balanced the mileage proportions between each. In 1956 the old Mersey trains were finally replaced by trains which were complete copies of the 1938 stock, by the same builders as before.

The Mersey used a 4-rail electric scheme, like London Underground, whereas the later Wirral scheme was 3rd rail, so both Mersey and Wirral trains had changeover switches for when at Birkenhead Park they ran on from one to the other, until finally standardised as 3rd rail throughout in the late 1950s.

With the flurry of recent threads on historic electrics around the north-west, I've just learned a quirky bit of trivia:-

When the Mersey Railway installed their fourth-rail electrification in 1903, there were no established standards for positioning a conductor rail with respect to the adjacent running rail. As it turned out, the Mersey company's live rail was installed closer than the standard subsequently specified in 1928 by the Pringle Report on railway electrification.

In the 1930s, when the LMS proposed the West Kirby & New Brighton electrification and through running to Liverpool via the Mersey Railway, the two company's conductor rails potentially would not align.

The Mersey Railway then had to reposition all of its live rail to meet the national standard ahead of the LMS lines "going live" and arrival of the Class 503s. The work was done at night in sections, taking a number of weeks. In the meantime the old Mersey Railway stock kept running as normal by temporarily using double sets of collector shoes to suit both 'old' and 'new' conductor rail positions. (Note this is separate to the 3rd versus 4th rail issue, which was solved by the automatic changeover procedure mentioned by @Taunton)